An investigation into electrochemical properties of poly(ether sulfone)/poly(vinyl pyrrolidone) heterogeneous cation-exchange membranes by using design of experiment method

Poly(ether sulfone) (PES)/poly(vinyl pyrrolidone) (PVP) blend heterogeneous cation exchange membranes were prepared by solution casting technique using dimethylformamide as solvent and cation exchange resin powder as functional groups agent. In this study, Taguchi experiment design method was employed for investigating the effects of controlling variables including polymer binder (PVP + PES) to total casting solution ratio, blend ratio of polymer binders (PVP to PES), resin to polymer binder ratio, and casting temperature on electrochemical characteristics of PES/PVP heterogeneous membranes. To this aim, each factor was considered at 4 different levels and therefore, 16 experiments were designed. To improve the quality of the membranes ultrasonic was used for appropriate dispersing of resin particles in the matrix of the membranes. According to the results, the averaged maximum values of 1.535 meq/g and 46.6 mV were obtained for IEC and membrane potential, respectively. Also, the highest obtained value of ion permeability tests was equal to 1.33 m/s. Finally, the synthesis conditions was optimized by considering the IEC and membrane potential as the objective functions which gave the values of 1.55 meq/g and 1.39 m/s for IEC and membrane potential, respectively, which proved that the synthesized membrane can be considered as a promising heterogeneous membrane.

The use of aortic balloon occlusion in traumatic shock: first report from the ABO trauma registry

PURPOSE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique for temporary stabilization of patients with non-compressible torso hemorrhage. This technique has been increasingly used worldwide during the past decade. Despite the good outcomes of translational studies, clinical studies are divided. The aim of this multicenter-international study was to capture REBOA-specific data and outcomes.

METHODS

REBOA practicing centers were invited to join this online register, which was established in September 2014. REBOA cases were reported, both retrospective and prospective. Demographics, injury patterns, hemodynamic variables, REBOA-specific data, complications and 30-days mortality were reported.

RESULTS

Ninety-six cases from 6 different countries were reported between 2011 and 2016. Mean age was 52 ± 22 years and 88% of the cases were blunt trauma with a median injury severity score (ISS) of 41 (IQR 29-50). In the majority of the cases, Zone I REBOA was used. Median systolic blood pressure before balloon inflation was 60 mmHg (IQR 40-80), which increased to 100 mmHg (IQR 80-128) after inflation. Continuous occlusion was applied in 52% of the patients, and 48% received non-continuous occlusion. Occlusion time longer than 60 min was reported as 38 and 14% in the non-continuous and continuous groups, respectively. Complications, such as extremity compartment syndrome (n = 3), were only noted in the continuous occlusion group. The 30-day mortality for non-continuous REBOA was 48%, and 64% for continuous occlusion.

CONCLUSIONS

This observational multicenter study presents results regarding continuous and non-continuous REBOA with favorable outcomes. However, further prospective studies are needed to be able to draw conclusions on morbidity and mortality.

Classification of Bitter Orange Essential Oils According to Fruit Ripening Stage by Untargeted Chemical Profiling and Machine Learning

The quality and composition of bitter orange essential oils (EOs) strongly depend on the ripening stage of the citrus fruit. The concentration of volatile compounds and consequently its organoleptic perception varies. While this can be detected by trained humans, we propose an objective approach for assessing the bitter orange from the volatile composition of their EO. The method is based on the combined use of headspace gas chromatography–mass spectrometry (HS-GC-MS) and artificial neural networks (ANN) for predictive modeling. Data obtained from the analysis of HS-GC-MS were preprocessed to select relevant peaks in the total ion chromatogram as input features for ANN. Results showed that key volatile compounds have enough predictive power to accurately classify the EO, according to their ripening stage for different applications. A sensitivity analysis detected the key compounds to identify the ripening stage. This study provides a novel strategy for the quality control of bitter orange EO without subjective methods.

Pentiptycene-Based Polyurethane with Enhanced Mechanical Properties and CO2-Plasticization Resistance for Thin Film Gas Separation Membranes

The development of thin film composite (TFC) membranes offers an opportunity to achieve the permeability/selectivity requirements for optimum CO₂ separation performance. However, the durability and performance of thin film gas separation membranes are mostly challenged by weak mechanical properties and high CO₂ plasticization. Here, we designed new polyurethane (PU) structures with bulky aromatic chain extenders that afford preferred mechanical properties for ultra-thin-film formation. An improvement of about 1500% in Young's modulus and 600% in hardness was observed for pentiptycene-based PUs compared to the typical PU membranes. Single (CO₂, H₂, CH₄, and N₂) and mixed (CO₂/N₂ and CO₂/CH₄) gas permeability tests were performed on the PU membranes. The resulting TFC membranes showed a high CO₂ permeance up to 1400 GPU (10^-6 cm³(STP) cm^-2 s^-1 cmHg^-1) and the CO₂/N₂ and CO₂/H₂ selectivities of about 22 and 2.1, respectively. The enhanced mechanical properties of pentiptycene-based PUs result in high-performance thin membranes with the similar selectivity of the bulk polymer. The thin film membranes prepared from pentiptycene-based PUs also showed a twofold enhanced plasticization resistance compared to non-pentiptycene-containing PU membranes.

Prevalence of UTI among Iranian infants with prolonged jaundice, and its main causes: A systematic review and meta-analysis study

INTRODUCTION

An extremely variable and high prevalence of urinary tract infection (UTI) in infants with prolonged jaundice has been reported in Iran. However, there is no research from the area that has attempted to estimate pooled prevalence of UTI from considerably diverse evidence. Therefore, this systematic review and meta-analysis study aimed to estimate the prevalence of UTI in infants with prolonged jaundice who were admitted into clinics or hospitals in Iran.

METHODS

A systematic review and meta-analysis was conducted of published articles on UTI prevalence in infants with prolonged jaundice in Iran. Electronic databases were searched, including Web of Sciences, PubMed/Medline, Scopus, Iranian Scientific Information Database (SID) and Iranmedex, for both English and Persian language articles published between January, 2000 and March, 2017. All possible combinations of the following keywords were used: jaundice, icterus, hyperbilirubinemia during infancy, infection and neonatal. Nine studies that reported prevalence of UTI in infants with prolonged jaundice were included. The overall prevalence of UTI was estimated using random-effects meta-analysis models.

RESULTS

A total of 1750 infants were pooled to estimate the overall prevalence of UTI in infants with prolonged jaundice. The prevalence reported by the studies included in this literature review was extremely variable and ranged 0.6-53.9%. The overall prevalence was 11% (95% Confidence Interval (CI): 5.0-18.0), and Escherichia coli was found to be the main cause of UTI.

CONCLUSION

The overall prevalence of UTI was 11%, and E. coli was the main cause of UTI in infants with prolonged jaundice. Screening of UTI should be considered for infants with prolonged jaundice.

Longitudinal association of metabolic syndrome and dietary patterns: A 13-year prospective population-based cohort study

BACKGROUND AND AIMS

Diet is a potential factor contributing to the development of the Metabolic Syndrome (MetS). This longitudinal study with repeated measurements of dietary intake was thus conducted to examine the longitudinal association between major dietary patterns and risk of MetS.

METHODS AND RESULTS

The study was conducted within the framework of the Isfahan Cohort Study (ICS), in which 1387 participants were followed from 2001 to 2013. Validated food frequency questionnaire, anthropometric measurements, blood pressure, fasting serum lipids and blood sugars were evaluated in three phases of the study. Mixed effect Logistic and Cumulative Logit regressions were applied to evaluate the longitudinal associations between dietary patterns change and MetS and number of MetS components. Three dietary patterns were identified: Healthy, Iranian and Western dietary patterns. After adjustment for potential confounders, the higher scores of Healthy diet were inversely associated with the risk of MetS and number of MetS components (OR: 0.50, 95% CI: 0.36-0.70, OR: 0.52, 95% CI: 0.39-0.70, respectively). The greater adherence to the Iranian diet was positively associated with the risk of MetS and number of MetS components (OR: 1.28, 95% CI: 1.01-1.65, OR: 1.45, 95% CI: 1.16-1.81, respectively). The Western dietary pattern did not show any significant associations.

CONCLUSION

Adherence to a Healthy diet was associated with lower risk of MetS even in a developing country setting. However, the Iranian diet was positively associated with the risk of MetS. These results may guide the development of improved preventive nutrition interventions in this adult population.

Overview and evaluation of different nuclear level density models for the 123I radionuclide production

The ¹²³I radionuclide (T_1/2 = 13.22 h, β+ = 100%) is one of the most potent gamma emitters for nuclear medicine. In this study, the cyclotron production of this radionuclide via different nuclear reactions namely, the ¹²¹Sb(α,2n), ¹²²Te(d,n), ¹²³Te(p,n), ¹²⁴Te(p,2n), ¹²⁴Xe(p,2n), ¹²⁷I(p,5n) and ¹²⁷I(d,6n) were investigated. The effect of the various phenomenological nuclear level density models such as Fermi gas model (FGM), Back-shifted Fermi gas model (BSFGM), Generalized superfluid model (GSM) and Enhanced generalized superfluid model (EGSM) moreover, the three microscopic level density models were evaluated for predicting of cross sections and production yield predictions. The SRIM code was used to obtain the target thickness. The ¹²³I excitation function of reactions were calculated by using of the TALYS-1.8, EMPIRE-3.2 nuclear codes and with data which taken from TENDL-2015 database, and finally the theoretical calculations were compared with reported experimental measurements in which taken from EXFOR database.

Investigation of the thermal performance of natTe target for 124I production in the RARS cyclotron

Regarding the low thermal conductivity of natTe element, the provision of an effective cooling system is one of the critical issues in cyclotron targetry to prevent melting of target matter during the irradiation to 124I production via natTe(p,xn)124I reaction. Heat transfer on Te target and efficiency of cooling fluid in the solid target system have been simulated based on a Finite Element Analysis (FEA) code for the thermal behavior of the target during the irradiation and under different beam currents, coolant flow rates, substrate matters and target geometry. The results on the routinely used solid target in Radiation Application Research School (RARS) cyclotron showed that in a 3 m/s coolant flow rate, by using a fined-cooling system and a nickel substrate coated on copper backing plate, the irradiation beam current can be raised up to 180 μA without any risk of melting. The cooling flow rates greater than 3 m/s do not noticeably improve the heat dispersion of target layer. As expected, a linear increase was observed for the temperature and temperature gradient of plates in the beam currents of 100–300 μA.

Association of pre- and early post-transplant serum amino acids and metabolites of amino acids and liver transplant outcome

The aim of the present study was to investigate association of serum amino (AA) acids and metabolites of AAs with post-transplant outcome in liver transplant recipients. Eighty-nine patients with end-stage liver diseases and available pre- and early post-transplant serum were characterised as patients with (GI) and without one-year mortality (GII) and patients with and without early graft dysfunction (EAD). A panel of pre- and early post-transplant serum levels of AAs and early and metabolites of tryptophan were measured using tandem mass spectrometry. Patient groups had significantly higher pre-transplant serum levels of phenylalanine, tryptophan, and tryptophan metabolites than healthy controls (for all p<0.001). Pre-transplant serum levels of all these parameters were significantly higher in GI than in GII (for all p<0.001). GI had a higher MELD score and re-transplantation number than GII (p≤0.005 for both investigations). Serum bilirubin on day 5 and serum phenylalanine on day 10 post-transplant were associated parameters of mortality, whereas day 1post-transplant phenylalanine and kynurenine and female gender were associated parameters of EAD. Our results indicate that pre- and early post-transplant levels of phenylalanine, tryptophan and metabolites of tryptophan are increased in patients and are associated with EAD and one-year mortality in liver transplant recipients.

Walking ability of spinal cord injury individuals: How to improve it?

BACKGROUND

Subjects with Spinal Cord Injury (SCI) should use various assistive devices to stand and walk. Unfortunately they suffer from slow walking speed, high energy consumption, and too much force applied on upper limb while walking. The aim of this study was to determine the gap between the gait performance of SCI and normal subjects to conclude how the performance of SCI can be improved.

METHOD

Three groups of SCI walked with orthosis, SCI walked without orthosis, and normal subjects were recruited in this study. The normal subjects also walked with the same orthoses as SCI subjects. Some parameters such as ranges of motion of hip, knee and spatiotemporal gait parameters were evaluated by use of Qualysis motion analysis system. The difference between the gait parameters of three groups were evaluated by use of two sample t test.

RESULTS

The mean values of hip joint range of motion of normal subjects while walking with and without orthosis were 48.3 ± 2.5 and 18.5 ± 8.8 degrees, respectively (p-value = 0.00). There was a significant difference between walking speed of normal subjects with and without orthosis. The walking speed of SCI subject with and without orthosis differed significantly.

CONCLUSION

Although use of orthosis enable SCI subjects to stand and walk, but has some restrictions. As use of orthosis decreased the abilities of normal subjects it can be concluded that more attention should be done on design of orthosis and style of walking.

A novel method of combined detector model for gamma-ray densitometer: Theoretical calculation and MCNP4C simulation

This study focuses on investigating a new model of combined backscatter and transmission method for nuclear densitometer. In this method for density measurement, a true combination of transmission and backscatter methods was studied and related equations were developed. The MCNP4C code was used for simulation of this combined detector model (CDM) and by applying theoretical calculations, density equation was corrected for the proposed nuclear densitometer. In the new method presented here, the buildup effect was estimated by an online system that was improved in our laboratory and was replaced by a new conceptual calculation. Hence, for the purpose of buildup reduction, there was no need for the shield around the detector, as it was monitored and reduced online. Furthermore, this study showed that the RSQ function could be improved by the CDM. The measurement technique proposed in this study has a better linearity trend than the transmission technique. Thus, the ability of CDM to improve the accuracy of the nuclear densitometer was shown.

Cardiovascular Risk Factors in Iranian Adults according to Educational Levels: Isfahan Healthy Heart Program

There is abundant evidence that the socioeconomic status (SES) is inversely associated with CVD risk factors. The objective of this study is to describe the distribution of CVD risk factors according to educational level in Iranian adults. A cross-sectional survey was performed on subjects over the age of 19 in three cities. Demographic data, as well as information on educational level and smoking habits was obtained and then height, weight and blood pressure measurement and blood sampling were arranged. Data was analyzed by the Mantel-Haenszel, Kendalls T correlation and multivariate analysis test. Of 9587 subjects, 48% were men and 52% were women, with mean ages of 39.0±15.3 and 38.8±14.5 years, respectively. All CVD risk factors showed an inverse relationship with educational level in all subjects, except for smoking and low HDL-C in women. High TC and LDL-C and low HDL-C were inversely related to educational level (P<0.05); however, this relationship was not significant with Mantel-Haenszel test in men. The association between CVD risk factors and educational level in women was stronger than in men. The differences found between CVD risk factors with educational level are important and should be considered in programs designed to increase level of education in order to lower CVD risk factors. Asia Pac J Public Health 2005: 17(1): 9-14.